Long-term efficacy and safety of iloperidone: results from 3 clinical trials for the treatment of schizophrenia

An Updated Safety Review of the Relationship Between Atypical Antipsychotic Drugs, the QTc Interval and Torsades de Pointe As: Implications for Clinical Use

INTRODUCTION

The rising prevalence of psychiatric disorders has resulted in a significant increase in the use of antipsychotic medications. These agents may prolong the corrected QT interval (QTc), running the risk of precipitating ventricular arrhythmias, notably Torsades de Pointes (TdP). Current recommendations vary regarding the optimal approach to safe prescribing practices and QTc surveillance for antipsychotics. This review summarizes the current literature addressing these clinical concerns.

AREAS COVERED

The physiologic basis of the QTc interval, mechanisms underlying its susceptibility to pharmacological influence, specific risks associated with atypical antipsychotic agents, and recommendations for safe prescription practices. We performed a literature review using Pubmed and Embase databases, searching for 'antipsychotics' and 'torsades de pointes.'

EXPERT OPINION

Finding a safe and universally accepted protocol for prescribing antipsychotics remains a persistent challenge in medicine. Predictive models that integrate clinical history with demographic and ECG characteristics can help estimate an individual's susceptibility to therapy-associated risks, including QTc prolongation. Agents such as ziprasidone and iloperidone are significantly more likely to prolong the QTc interval compared to others such as brexpiprazole, cariprazine, olanzapine, and clozapine. A personalized approach using low-risk medications when clinically feasible, and at the lowest efficacious dose, offers a promising path toward safer antipsychotic prescribing.

An update on the efficacy and safety of iloperidone as a schizophrenia therapy

INTRODUCTION

Schizophrenia has a prevalence of approximately 1% in the general population, with 15.2 per 100,000 persons affected. Iloperidone is a second-generation antipsychotic drug approved for the treatment of schizophrenia in adults. It acts primarily by D2/5HT2a receptor antagonism, with greater affinity for the 5HT2a receptor than for the D2 receptor.

AREAS COVERED

This article discusses iloperidone and aims to provide useful information for clinicians to determine which circumstances would best suit the use of iloperidone to treat schizophrenic patients. In this review, the authors briefly discuss schizophrenia and its treatment, before they discuss properties of iloperidone, its indications, approval process, and adverse effects. Finally, the authors review the specific strengths and weaknesses of the medication.

EXPERT OPINION

Iloperidone would be an attractive option in patients who are particularly prone to EPS, or who are showing prominent negative symptoms, as well as cognitive deficits. Its availability only in an oral formulation makes it a better option for patients with good medication adherence, and though it could be useful in patients prone to weight gain or hepatic dysfunction on other second generation antipsychotics, it should be used with caution in patients prone to side effects related to alpha adrenergic blockade.

British Heart Rhythm Society Clinical Practice Guidelines on the Management of Patients Developing QT Prolongation on Antipsychotic Medication

The British Heart Rhythm Society’s Clinical Practice Guidelines on the Management of Patients Developing QT Prolongation on Antipsychotic Medication are written for heart rhythm consultants, primary care physicians, specialist registrars, nurses and physiologists who may be requested to review ECGs or advise on cases where antipsychotic-induced QT prolongation is suspected or proven. The guidance is adapted from the latest Maudsley Prescribing Guidelines in Psychiatry, published in 2018.

Medication-Induced Akathisia with Newly Approved Antipsychotics in Patients with a Severe Mental Illness: A Systematic Review and Meta-Analysis

BACKGROUND

Akathisia is a common and distressing movement disorder that can be associated with the use of antipsychotics. It is characterized by a subjective (inner restlessness) and an objective (excessive movements) component. Akathisia can have a negative impact on clinical outcome and even lead to treatment discontinuation. Although medication-induced akathisia is more commonly associated with the use of first-generation antipsychotics (FGAs), it also occurs with second-generation antipsychotics (SGAs), including the newly approved antipsychotics (NAPs) asenapine, lurasidone, iloperidone, cariprazine, and brexpiprazole. Until now, no meta-analysis has been published on the risk of akathisia for all NAPs, as monotherapy or adjunctive treatment, in patients with a severe mental illness.

OBJECTIVE

The primary objectives of this systematic review and meta-analysis were to (i) compare akathisia incidence rates of the NAPs, as monotherapy or adjunctive treatment, in adult patients with a severe mental illness (i.e., schizophrenia, bipolar disorder, or major depressive disorder), using data from published and unpublished randomized controlled trials; and (ii) examine the role of several study characteristics explaining differences in akathisia incidence rates between studies.

METHODS

A systematic literature search, using the PubMed, EMBASE, and Cochrane Library databases (until October 2018), was conducted for English-language placebo- as well as active-controlled clinical trials, including subjective (percentage of patients reporting akathisia) and/or scale-defined medication-induced akathisia incidence rates with NAPs (as monotherapy or as adjunctive treatment) in adult patients with schizophrenia, bipolar disorder, or major depressive disorder. Additional unpublished clinical trials were identified through the ClinicalTrials.gov electronic database. Two meta-analyses (incidence rates and odds ratio [OR] [placebo vs. active] of medication-induced akathisia with NAPs) were performed to obtain an optimal estimation of akathisia risks of adult patients with a severe mental illness under these treatment conditions and to assess the role of study characteristics.

RESULTS

Two hundred and thirteen reports were selected as potentially eligible for our meta-analysis. Of these, 48 met the inclusion criteria. Eight records, identified through the ClinicalTrials.gov database and cross-referencing, and which fulfilled the inclusion criteria, were added, resulting in a total of 56 records (iloperidone = 5, asenapine = 11, lurasidone = 15, brexpiprazole = 13, cariprazine = 12). The estimated weighted mean incidence rate of akathisia was 7.7% (95% confidence interval [CI] 6.5-9.1), with estimates being 3.9% (95% CI 2.4-6.3) for iloperidone, 6.8% (95% CI 5.1-9.0) for asenapine, 10.0% (95% CI 7.4-13.5) for brexpiprazole, 12.7% (95% CI 10.1-16.1) for lurasidone, and 17.2% (95% CI 13.4-22.1) for cariprazine. After Tukey-adjustment for multiple testing, the incidence rate of akathisia was significantly (p < 0.05) lower for iloperidone than for brexpiprazole, lurasidone, and cariprazine. In addition, the incidence rate of akathisia was significantly (p < 0.05) lower for asenapine than for lurasidone and cariprazine. Finally, the incidence rate of akathisia was significantly (p < 0.05) lower for brexpiprazole than for cariprazine. Type of medication (p < 0.0001), diagnosis (p = 0.02), and race (p = 0.0003) significantly explained part of the heterogeneity of the incidence estimates of akathisia between studies. The estimated weighted OR of akathisia under medication, compared with placebo, was 2.43 (95% CI 1.91-3.10). The OR was smallest for iloperidone (OR 1.20; 95% CI 0.42-3.45) and increased for brexpiprazole (OR 2.04; 95% CI 1.09-3.83), asenapine (OR 2.37; 95% CI 1.32-4.27), lurasidone (OR 3.74; 95% CI 2.32-6.02), and cariprazine (OR 4.35; 95% CI 2.80-6.75). Only type of medication (p = 0.03) explained systematic differences in the OR for akathisia between placebo versus active treatment across studies. After Tukey-adjustment for multiple testing, no significant differences between these ORs were found. The severity of akathisia with NAPs generally is mild to moderate, only leading to treatment discontinuation in a minority of cases (< 5%).

CONCLUSIONS

The use of a NAP raises the akathisia risk more than two-fold when compared with patients receiving placebo. Although distinctions between the different NAPs were not clear in placebo-controlled trials, the results of our meta-analyses and systematic review generally indicate that these differences more than likely reflect real differences, with iloperidone showing the most and cariprazine showing the least benign akathisia profile. Moreover, due to patient characteristics and methodological issues, incidence rates of akathisia with NAPs found in this meta-analysis may even be an underestimation of true incidence rates.

An Open Trial of Iloperidone for Mixed Episodes in Bipolar Disorder

BACKGROUND

Mixed mood states in bipolar disorder are difficult to treat and when present indicate worse illness trajectories. Several medications are US Food and Drug Administration approved to treat mixed episodes; however, the clinical trials have been short term and rarely reported depression response.

METHODS

We conducted a 5-month open-label trial examining the tolerability and efficacy of iloperidone for bipolar disorder mixed episodes.

RESULTS

Mania and depression scores significantly improved over the course of the study for study completers (ie, 60%-68% improvement for manic symptoms and 41%-49% for depression symptoms). Improvements were observed early in the trial and after adjusting for concomitant medication effects. The average daily dose in completers was 15 mg. Thirty-nine percent (12/31) of the eligible sample discontinued early because of adverse effects. The adverse events most commonly associated with withdrawal were increased heart rate/palpitations (n = 5 of 12) and urinary incontinence/intense urge to urinate (n = 3 of 12).

CONCLUSIONS

In a subset of patients, iloperidone provides relief for classic manic, depression, and irritability symptoms associated with mixed episodes in a long-term trial. Adverse effect profiles are likely to be a major factor contributing to individualized medication use.

Current and potential pharmacological and psychosocial interventions for anxiety symptoms and disorders in patients with schizophrenia: structured review

OBJECTIVE

Between 30% and 62% of patients with schizophrenia present with co-morbid anxiety disorders that are associated with increased overall burden. Our aim was to summarize current and potential interventions for anxiety in schizophrenia.

DESIGN

Structured review, summarizing pharmacological and psychosocial interventions used to reduce anxiety in schizophrenia and psychosis.

RESULTS

Antipsychotics have been shown to reduce anxiety, increase anxiety, or have no effect. These may be augmented with another antipsychotic, anxiolytic, or antidepressant. Novel agents, such as L-theanine, pregabalin, and cycloserine, show promise in attenuating anxiety in schizophrenia. Psychosocial therapies have been developed to reduce the distress of schizophrenia. Cognitive behavioural therapy (CBT) has shown that benefit and refinements in the therapy have been successful, for example, for managing worry in schizophrenia. CBT usually involves more than 16 sessions, as short courses of CBT do not attenuate the presentation of anxiety in schizophrenia. To address time and cost, the development of manualized CBT to address anxiety in schizophrenia is being developed.

CONCLUSIONS

The presence of coexisting anxiety symptoms and co-morbid anxiety disorders should be ascertained when assessing patients with schizophrenia or other psychoses as a range of pharmacological and psychosocial treatments are available.

Iloperidone in the treatment of schizophrenia: an evidence-based review of its place in therapy

Introduction

Schizophrenia is a chronic and debilitating mental disorder that affects the patient’s and their family’s quality of life, as well as financial costs and health care settings. Despite the variety of available antipsychotics, optimal treatment outcomes are not always achieved. Novel drugs, such as iloperidone, can provide more effective, tolerable and safer strategies.

Aim

To review the evidence for the clinical impact of iloperidone on the treatment of patients with schizophrenia.

Evidence review

Clinical trials, observational studies and meta-analyses reached a common consensus that iloperidone is as effective as haloperidol, risperidone and ziprasidone in reducing schizophrenia symptoms. Similar amounts of adverse events and discontinuations were observed with iloperidone compared to placebo and active treatments. Common adverse events are mild and include dizziness, hypotension, dry mouth and weight gain. Iloperidone can induce extension of QTc interval, and clinicians should be aware of its contraindications. In long-term trials, iloperidone also showed promising safety and tolerability profiles. The low propensity to cause akathisia, extrapyramidal symptoms (EPS), increased prolactin levels or changes to metabolic laboratory parameters support its use in practice. Results showed that iloperidone prevents relapse in stabilized patients, with a time to relapse superior to placebo and similar to haloperidol. Patients using a prior antipsychotic (eg, risperidone and aripiprazole) can easily switch to iloperidone with no serious impact on safety or efficacy. However, the acquisition costs of iloperidone may hamper its use. Further evidence comparing iloperidone with other antipsychotics, and pharmacoeconomic studies would be welcome.

Place in therapy

Considering just the clinical profile of iloperidone, it represents a promising drug for treating schizophrenia, particularly in patients who are intolerant to previous antipsychotics, as well as being suitable as first-line therapy. Cost-effectiveness comparisons are needed to justify its use in clinical practice.

5-HT2C receptors in psychiatric disorders: A review

5-HT2Rs have a different genomic organization from other 5-HT2Rs. 5HT2CR undergoes post-transcriptional pre-mRNA editing generating diversity among RNA transcripts. Selective post-transcriptional editing could be involved in the pathophysiology of psychiatric disorders through impairment in G-protein interactions. Moreover, it may influence the therapeutic response to agents such as atypical antipsychotic drugs. Additionally, 5-HT2CR exhibits alternative splicing. Central serotonergic and dopaminergic systems interact to modulate normal and abnormal behaviors. Thus, 5HT2CR plays a crucial role in psychiatric disorders. 5HT2CR could be a relevant pharmacological target in the treatment of neuropsychiatric disorders. The development of drugs that specifically target 5-HT2C receptors will allow for better understanding of their involvement in the pathophysiology of psychiatric disorders including schizophrenia, anxiety, and depression. Among therapeutic means currently available, most drugs used to treat highly morbid psychiatric diseases interact at least partly with 5-HT2CRs. Pharmacologically, 5HT2CRs, have the ability to generate differentially distinct response signal transduction pathways depending on the type of 5HT2CR agonist. Although this receptor property has been clearly demonstrated, in vitro, the eventual beneficial impact of this property opens new perspectives in the development of agonists that could activate signal transduction pathways leading to better therapeutic efficiency with fewer adverse effects.

A Randomized Trial of Iloperidone for Prevention of Relapse in Schizophrenia: The REPRIEVE Study

BACKGROUND

The purpose of this study was to evaluate the safety and effectiveness of iloperidone for the prevention of relapse in schizophrenia.

METHODS

Study subjects were adults with schizophrenia who started on oral open-label iloperidone titrated to an initial target dose of 12 mg/day (6 mg twice daily) and then stabilized on a flexible-dose iloperidone regimen (range 8-24 mg/day) for up to 24 weeks. Subjects meeting stabilization criteria then entered the relapse-prevention phase and were randomized 1:1 in a double-blind fashion to continue with iloperidone or placebo withdrawal for up to 26 weeks or until meeting relapse or other withdrawal criteria.

RESULTS

A total of 303 subjects were randomized to the relapse-prevention phase; 153 continued to receive iloperidone, and 150 were withdrawn to placebo. The modal total daily dose for iloperidone in all phases of the study was 12 mg/day. The pre-defined unblinded interim analysis upon reaching 68 relapse events confirmed the hypothesis that iloperidone (n = 97) was more effective than placebo (n = 96) in preventing relapse events, and the trial was stopped early. The estimated relapse rates were 63.4 % (Kaplan-Meier [KM] estimate) for placebo compared with 20.4 % (KM estimate) for those continuing to receive iloperidone (log rank test: p < 0.0001). The mean time to relapse was 71 days for placebo and 139 days for iloperidone (hazard ratio 4.7; 95 % confidence interval 2.7-8.3; p < 0.0001). The safety profile observed in previous short-term studies was also reaffirmed in this maintenance treatment setting. The most common treatment-emergent adverse events (TEAEs) in the stabilization phase were dizziness (11.6 %), somnolence (8.3 %), and dry mouth (6.8 %). Rates of reported extrapyramidal disorder or akathisia during stabilization were 2.5 and 3.7 %, respectively.

CONCLUSIONS

Flexible dosing of iloperidone for maintenance-phase therapy, with a modal dose of 12 mg/day was effective in preventing relapse in subjects previously stabilized on iloperidone. The adverse event profile for iloperidone was consistent with other studies, and the low extrapyramidal symptom and akathisia burden during stabilization was sustained during the course of the study. ClinicalTrials.gov identifier: NCT01291511.

Clinical factors related to schizophrenia relapse

OBJECTIVE

Relapses represent one of the main problems of schizophrenia management. This article reviews the clinical factors associated with schizophrenia relapse.

METHODS

A research of the last 22 years of literature data was performed. Two-hundred nineteen studies have been included.

RESULTS

Three main groups of factors are related to relapse: factors associated with pharmacological treatment, add-on psychotherapeutic treatments and general risk factors. Overall, the absence of a maintenance therapy and treatment with first generation antipsychotics has been associated with higher risk of relapse. Further, psychotherapy add-on, particularly with cognitive behaviour therapy and psycho-education for both patients and relatives, has shown a good efficacy for reducing the relapse rate. Among general risk factors, some could be modified, such as the duration of untreated psychosis or the substance misuse, while others could not be modified as male gender or low pre-morbid level of functioning.

CONCLUSION

Several classes of risk factors have been proved to be relevant in the risk of relapse. Thus, a careful assessment of the risk factors here identified should be performed in daily clinical practice in order to individualise the relapse risk for each patient and to provide a targeted treatment in high-risk subjects.

The quality of reporting of phase II and III trials for new antipsychotics: a systematic review

BACKGROUND

The findings of the Clinical Antipsychotic Trials of Intervention Effectiveness (CATIE) study and the Cost Utility of the Latest Antipsychotic Drugs in Schizophrenia Study (CUtLASS) called previous trials of antipsychotics into question, including pre-licensing trials. Concerns regarding methodological robustness and quality of reporting increased. This systematic review aimed to examine the quality of reporting of phase II and III trials for new antipsychotics in the aftermath of the CATIE and CUtLASS studies.

METHOD

Electronic searches were conducted in EMBASE, Medline and Cochrane databases and also ClinicalTrials.gov for antipsychotic trials (published between January 2006 and February 2012). Phase II and III randomized controlled trials (RCTs) for iloperidone, asenapine, paliperidone, olanzapine, lurasidone and pomaglumetad methionil were selected for schizophrenia and schizoaffective disorder. The reporting of the methodology was evaluated in accordance with Consolidated Standards of Reporting Trials (CONSORT) guidelines.

RESULTS

Thirty-one articles regarding 32 studies were included. There was insufficient reporting of design in 47% of studies and only 13% explicitly stated a primary hypothesis. Exclusion criteria were poorly reported for diagnosis in 22% of studies. Detail regarding comparators, particularly placebos, was suboptimal for 56% of studies, and permitted concomitant medication was often not reported (19%). Randomization methods were poorly described in 56% of studies and reporting on blinding was insufficient in 84% of studies. Sample size calculations were insufficiently reported in 59% of studies.

CONCLUSIONS

The quality of reporting of phase II and III trials for new antipsychotics does not reach the standards outlined in the CONSORT guidelines. Authors often fail to adequately report design and methodological processes, potentially impeding the progress of research on antipsychotic efficacy. Both policymakers and clinicians require high quality reporting before decisions are made regarding licensing and prescribing of new antipsychotics.

QTc interval prolongation and torsade de pointes associated with second-generation antipsychotics and antidepressants: a comprehensive review

We comprehensively reviewed published literature to determine whether it supported the link between corrected QT (QTc) interval prolongation and torsade de pointes (TdP) for the 11 second-generation antipsychotics and seven second-generation antidepressants commonly implicated in these complications. Using PubMed and EMBASE, we identified four thorough QT studies (one each for iloperidone, ziprasidone, citalopram, and escitalopram), 40 studies specifically designed to assess QTc interval prolongation or TdP, 58 publications based on data from efficacy and safety trials, 18 toxicology studies, and 102 case reports. Thorough QT studies, QTc prolongation-specific studies, and studies based on efficacy and safety trials did not link drug-associated QTc interval prolongation with TdP. They only showed that the drugs reviewed caused varying degrees of QTc interval prolongation, and even that information was not clear and consistent enough to stratify individual drugs for this risk. The few toxicology studies provided valuable information but their findings are pertinent only to situations of drug overdose. Case reports were most informative about the drug-QTc interval prolongation-TdP link. At least one additional well established risk factor for QTc prolongation was present in 92.2 % of case reports. Of the 28 cases of TdP, six (21.4 %) experienced it with QTc interval <500 ms; 75 % of TdP cases occurred at therapeutic doses. There is little evidence that drug-associated QTc interval prolongation by itself is sufficient to predict TdP. Future research needs to improve its precision and broaden its scope to better understand the factors that facilitate or attenuate progression of drug-associated QTc interval prolongation to TdP.

Systematic review of long-acting injectables versus oral atypical antipsychotics on hospitalization in schizophrenia

OBJECTIVE

To assess the impact of long-acting injectables (LAIs) versus oral antipsychotics (OAs) on hospitalizations among patients with schizophrenia by conducting a systematic literature review of studies with different study designs and performing a meta-analysis.

METHODS

Using the PubMed database and major psychiatric conference proceedings, a systematic literature review for January 2000 to July 2013 was performed to identify English-language studies evaluating schizophrenia patients treated with atypical antipsychotics. Studies reporting hospitalization rates as a percentage of patients hospitalized or as the number of hospitalizations per person per year were selected. The primary meta-analysis assessed the percentage decrease in hospitalization rates before and after treatment initiation for matched time periods. The secondary meta-analysis assessed the absolute rate of hospitalization during follow-up. Pooled treatment-effect estimates were calculated using random-effects models. To account for differences in patient and study-level characteristics between studies, meta-regression analyses were used. Subset analyses further explored the heterogeneity across study designs.

RESULTS

Fifty-eight studies evaluating 25 arms (LAIs: 13 arms, 4516 patients; OAs: 12 arms, 23,516 patients) in the primary meta-analysis and 78 arms (LAIs: 12 arms, 4481 patients; OAs: 66 arms, 96,230 patients) in the secondary meta-analysis were identified. Reduction in hospitalization rates for LAIs was 20.7 percentage points higher than that of OAs (random-effects estimates: LAIs = 56.2% vs. OAs = 35.5%, P = 0.023). Controlling for patient and study characteristics, the adjusted percentage reduction in hospitalization rates for LAIs was 26.4 percentage points higher than for OAs (95% CI: 3.3-49.5, P = 0.027). As for the secondary meta-analysis, no significant difference between LAIs and OAs was observed (random-effects estimate: -8.6, 95% CI: -18.1-1.0, P = 0.077). Subset analyses across type of study yielded consistent results. Limitations of this analysis include the long observation period, which may not reflect current treatment patterns, the use of all-cause hospitalization, which may not be solely related to schizophrenia, and the fact that most studies in the LAI cohort evaluated risperidone.

CONCLUSION

The primary results of this meta-analysis, including studies with both interventional and non-interventional designs and using meta-regressions, suggest that LAIs are associated with higher reductions in hospitalization rates for schizophrenia patients compared to OAs.

Almost all antipsychotics result in weight gain: a meta-analysis

Introduction

Antipsychotics (AP) induce weight gain. However, reviews and meta-analyses generally are restricted to second generation antipsychotics (SGA) and do not stratify for duration of AP use. It is hypothesised that patients gain more weight if duration of AP use is longer.

Method

A meta-analysis was conducted of clinical trials of AP that reported weight change. Outcome measures were body weight change, change in BMI and clinically relevant weight change (7% weight gain or loss). Duration of AP-use was stratified as follows: ≤6 weeks, 6–16 weeks, 16–38 weeks and >38 weeks. Forest plots stratified by AP as well as by duration of use were generated and results were summarised in figures.

Results

307 articles met inclusion criteria. The majority were AP switch studies. Almost all AP showed a degree of weight gain after prolonged use, except for amisulpride, aripiprazole and ziprasidone, for which prolonged exposure resulted in negligible weight change. The level of weight gain per AP varied from discrete to severe. Contrary to expectations, switch of AP did not result in weight loss for amisulpride, aripiprazole or ziprasidone. In AP-naive patients, weight gain was much more pronounced for all AP.

Conclusion

Given prolonged exposure, virtually all AP are associated with weight gain. The rational of switching AP to achieve weight reduction may be overrated. In AP-naive patients, weight gain is more pronounced.

A trial evaluating gradual- or immediate-switch strategies from risperidone, olanzapine, or aripiprazole to iloperidone in patients with schizophrenia

In a 12-week randomized open-label trial, adults diagnosed with schizophrenia experiencing inadequate efficacy and/or poor tolerability on risperidone, olanzapine, or aripiprazole were randomized to switch to iloperidone either gradually (ie, down-titration of current therapy over the first 2weeks [to 50% on Day 1, 25% by Week 1, 0% by Week 2]) or immediately. All patients were titrated on iloperidone to 6mg BID by Day 4, then flexibly dosing between 6 and 12mg BID, as needed. The primary variable was the Integrated Clinical Global Impression of Change (I-CGI-C) and the primary analysis time point was Week 12. A total of 500 patients were randomized and received iloperidone (gradual switch, 240; immediate switch, 260), with 175, 155, and 170 patients switched from risperidone, olanzapine, and aripiprazole, respectively. I-CGI-C Results confirmed improved outcomes at Week 12, with scores that were similar between the gradual- and immediate-switch groups, respectively, for risperidone, 2.82 and 2.67 (95% CI: -0.229, 0.511); olanzapine, 2.87 and 3.03 (95% CI: -0.548, 0.235); and aripiprazole, 2.79 and 2.81 (95% CI: -0.405, 0.368). Incidence of adverse events (AEs) was similar in both switch groups, with the most frequently reported (≥10%) being dizziness, dry mouth, somnolence, and weight increase. In conclusion, switching to iloperidone by either a gradual or an immediate method did not reveal any clinically significant differences in ratings of overall efficacy and safety/tolerability outcomes, based on the I-CGI-C at 12weeks. Similar overall safety/AE profiles were observed regardless of the specific agent from which patients were switched.

Long-term efficacy and safety of iloperidone: an update

Schizophrenia is a devastating neuropsychiatric disease with a worldwide prevalence of approximately 0.5%-1%. Since many patients do not achieve adequate symptom relief from available agents, alternate pharmacotherapeutic approaches are needed. In this context, iloperidone was recently approved by the US Food and Drug Administration for the treatment of schizophrenia. This paper first reviews its pharmacodynamic and pharmacokinetic profiles, emphasizing their clinical relevance. Next, it summarizes the literature on its acute and maintenance efficacy, safety, and tolerability. It then considers pharmacogenetic data which may help to predict response and risk of cardiac arrhythmias with this agent. Finally, it critically positions iloperidone relative to other first- and second-generation antipsychotics.

Safety profile of iloperidone in the treatment of schizophrenia

INTRODUCTION

Iloperidone is a novel antipsychotic medication approved for the treatment of schizophrenia in adults with efficacy similar to its class counterparts. The purpose of this article is to describe the safety profile of iloperidone and its clinical implications.

AREAS COVERED

A PubMed search was undertaken on May 10, 2013, using the keyword iloperidone. Of the 121 articles that resulted, those with primary sources of information, along with secondary sources with an emphasis on drug safety, were included in this article. Iloperidone was found to have lower extrapyramidal symptom (EPS) and akathisia rates compared to haloperidol and risperidone. Twelve percent of patients experienced clinically significant weight gain, largely during initiation phase of treatment. No other clinically significant metabolic abnormalities were observed. QTc interval was increased by 10 ms, comparable to the effect observed with ziprasidone. QTc prolongation was heightened under inhibition of CYP2D6 and CYP3A4. Orthostatic hypotension was a common effect seen in the first week of treatment.

EXPERT OPINION

The favorable EPS and akathisia profile of iloperidone makes it an attractive choice for patients whose compliance is limited by these effects. However, the slow titration schedule adapted to reduce orthostasis may limit the use of this agent in an acute setting.

A review of the pharmacology, efficacy and tolerability of recently approved and upcoming oral antipsychotics: an evidence-based medicine approach

Evidence-based medicine (EBM) is a broad concept, but the key elements include the incorporation of clinical judgment (which requires clinical experience) together with relevant scientific evidence while remaining mindful of the individual patient's values and preferences. Using the framework and philosophy of EBM, this systematic review summarizes the pharmacology, efficacy, and tolerability of newly approved oral antipsychotics, including iloperidone, asenapine, and lurasidone, and outlines what is known about agents that are in late-stage clinical development, such as cariprazine, brexpiprazole, zicronapine, bitopertin, and EVP-6124. Potential advantages and disadvantages of these agents over existing antipsychotics are outlined, centered on clinically relevant issues such as the potential for weight gain and metabolic abnormalities, potential association with somnolence/sedation, extra-pyramidal side effects, akathisia, and prolongation of the electrocardiogram (ECG) QT interval, as well as practical issues regarding dosing instructions, titration requirements, and drug-drug interactions. Lurasidone appears to be best in class in terms of minimizing untoward alterations in body weight and metabolic variables. However, iloperidone, asenapine, lurasidone, and cariprazine differ among themselves in terms of on-label dosing frequency (once daily for lurasidone and, presumably, cariprazine versus twice daily for iloperidone and asenapine), the need for initial titration to a therapeutic dose for iloperidone and possibly cariprazine, requirement to be taken sublingually for asenapine, requirement for administration with food for lurasidone, lengthening of the ECG QT interval (greater for iloperidone than for asenapine and no effect observed with lurasidone), and adverse effects such as akathisia (seen with cariprazine, lurasidone, and asenapine but not with iloperidone) and sedation (most notable with asenapine).

Withdrawal symptoms and rebound syndromes associated with switching and discontinuing atypical antipsychotics: theoretical background and practical recommendations

With the widespread use of atypical or second-generation antipsychotics, switching treatment has become current practice and more complicated, as the pharmacological profiles of these agents differ substantially despite their similarity in being 'atypical'. All share the ability to block dopamine D₂ receptors, and most of them also block serotonin 5-HT2A receptors. Apart from these common features, some atypical antipsychotics are also able to block or stimulate other dopamine or serotonin receptors, as well as histaminergic, muscarinergic or adrenergic receptors. As a result of the varying receptor affinities, in switching or discontinuing compounds several possible pitfalls have to be considered, including the occurrence of withdrawal and rebound syndromes. This article reviews the pharmacological background of functional blockade or stimulation of receptors of interest in regard to atypical antipsychotics and the implicated potential withdrawal and rebound phenomena. A MEDLINE search was carried out to identify information on withdrawal or rebound syndromes occurring after discontinuation of atypical antipsychotics. Using the resulting literature, we first discuss the theoretical background to the functional consequences of atypical antipsychotic-induced blockade or stimulation of neurotransmitter receptors and, secondly, we highlight the clinical consequences of this. We then review the available clinical literature on switching between atypical antipsychotics, with respect to the occurrence of withdrawal or rebound symptoms. Finally, we offer practical recommendations based on the reviewed findings. The systematic evaluation of withdrawal or rebound phenomena using randomized controlled trials is still understudied. Knowledge of pharmacological receptor-binding profiles may help clinicians in choosing adequate switching or discontinuation strategies for each agent. Results from large switching trials indicate that switching atypical antipsychotics can be performed in a safe manner. Treatment-emergent adverse events during or after switching are not always considered to be, at least in part, associated with the pre-switch antipsychotic. Further studies are needed to substantiate the evidence gained so far on different switching strategies. The use of concomitant medication, e.g., benzodiazepines or anticholinergic drugs, may help to minimize symptoms arising from the discontinuation or switching of antipsychotic treatment.

Asenapine, iloperidone and lurasidone: critical appraisal of the most recently approved pharmacotherapies for schizophrenia in adults

This article reviews the pharmacological profile and published efficacy and tolerability/safety data of iloperidone, asenapine and lurasidone, the most recent atypical antipsychotics to be approved in the USA for the treatment of schizophrenia. All three agents are similar in terms of overall efficacy and low propensity for clinically significant weight gain or adverse changes in glycemic or lipid profile. However, these agents differ from one another in terms of formulations, pharmacokinetics, and dosing and nonmetabolic adverse effect profile. For each drug, comparative and real-world effectiveness studies are lacking, as are effectiveness and safety data in elderly, young and pregnant/nursing patients. As such, the exact place of iloperidone, asenapine and lurasidone within the broader antipsychotic armamentarium is currently difficult to establish.

Newer antipsychotics and upcoming molecules for schizophrenia

BACKGROUND

The management of schizophrenia has seen significant strides over the last few decades, due to the increasing availability of a number of antipsychotics. Yet, the diminished efficacy in relation to the negative and cognitive symptoms of schizophrenia, and the disturbing adverse reactions associated with the current antipsychotics, reflect the need for better molecules targeting unexplored pathways.

PURPOSE

To review the salient features of the recently approved antipsychotics; namely, iloperidone, asenapine, lurasidone and blonanserin.

METHODS

We discuss the advantages, limitations and place in modern pharmacotherapy of each of these drugs. In addition, we briefly highlight the new targets that are being explored.

RESULTS

Promising strategies include modulation of the glutamatergic and GABAergic pathways, as well as cholinergic systems.

CONCLUSIONS

Although regulatory bodies have approved only a handful of antipsychotics in recent years, the wide spectrum of targets that are being explored could eventually bring out antipsychotics with improved efficacy and acceptability, as well as the potential to revolutionize psychiatric practice.

Long-term safety and tolerability of iloperidone: results from a 25-week, open-label extension trial

INTRODUCTION/OBJECTIVE

Long-term use of the atypical antipsychotic iloperidone has not been investigated at doses above 16 mg/d. This article describes safety and tolerability results from the 25-week open-label extension of a 4-week placebo- and ziprasidone-controlled clinical trial of iloperidone.

METHODS

Patients received a dose of 24 mg/d (given as 12 mg twice daily; mean dose = 21.6 mg) that could be reduced to 12 mg/d (given once daily at bedtime) any time after day 35 at the investigator's discretion.

RESULTS

A total of 72/173 patients (41.6%) completed the open-label extension. Treatment-emergent adverse events (TEAEs), most mild to moderate in severity, included headache (13.9%), weight increase (9.2%), dizziness (6.9%), nausea (6.4%), sedation (6.4%), and insomnia (5.2%). The only notable dose-related TEAEs were increased weight and headache. Levels of serum glucose, lipids, and prolactin were essentially unchanged or decreased during treatment. In general, akathisia and extrapyramidal symptoms (EPS) improved or were unchanged during treatment. There was no signal of worsening of efficacy based on changes from baseline in the Positive and Negative Syndrome Scale-Total.

DISCUSSION/CONCLUSION

This study further supports the long-term safety and tolerability of iloperidone for the treatment of schizophrenia, including iloperidone's favorable effect on metabolic laboratory parameters and low propensity to cause akathisia or EPS.

Metabolic side-effects of the novel second-generation antipsychotic drugs asenapine and iloperidone: a comparison with olanzapine

Background

The second generation antipsychotic (SGA) drugs are widely used in psychiatry due to their clinical efficacy and low incidence of neurological side-effects. However, many drugs in this class cause deleterious metabolic side-effects. Animal models accurately predict metabolic side-effects for SGAs with known clinical metabolic liability. We therefore used preclinical models to evaluate the metabolic side-effects of glucose intolerance and insulin resistance with the novel SGAs asenapine and iloperidone for the first time. Olanzapine was used as a comparator.

Methods

Adults female rats were treated with asenapine (0.01, 0.05, 0.1, 0.5, 1.0 mg/kg), iloperidone (0.03, 0.5, 1.0, 5.0, 10.0 mg/kg) or olanzapine (0.1, 0.5, 1.5, 5.0, 10.0 mg/kg) and subjected to the glucose tolerance test (GTT). Separate groups of rats were treated with asenapine (0.1 and 1.0 mg/kg), iloperidone (1.0 and 10 mg/kg) or olanzapine (1.5 and 15 mg/kg) and tested for insulin resistance with the hyperinsulinemic-euglycemic clamp (HIEC).

Results

Asenapine showed no metabolic effects at any dose in either test. Iloperidone caused large and significant glucose intolerance with the three highest doses in the GTT, and insulin resistance with both doses in the HIEC. Olanzapine caused significant glucose intolerance with the three highest doses in the GTT, and insulin resistance with the higher dose in the HIEC.

Conclusions

In preclinical models, asenapine shows negligible metabolic liability. By contrast, iloperidone exhibits substantial metabolic liability, comparable to olanzapine. These results emphasize the need for appropriate metabolic testing in patients treated with novel SGAs where current clinical data do not exist.

Relapse prevention in schizophrenia: a systematic review and meta-analysis of second-generation antipsychotics versus first-generation antipsychotics

Few controlled trials compared second-generation antipsychotics (SGAs) with first-generation antipsychotics (FGAs) regarding relapse prevention in schizophrenia. We conducted a systematic review/meta-analysis of randomized trials, lasting 6 months comparing SGAs with FGAs in schizophrenia. Primary outcome was study-defined relapse; secondary outcomes included relapse at 3, 6 and 12 months; treatment failure; hospitalization; and dropout owing to any cause, non-adherence and intolerability. Pooled relative risk (RR) (±95% confidence intervals (CIs)) was calculated using random-effects model, with numbers-needed-to-treat (NNT) calculations where appropriate. Across 23 studies (n=4504, mean duration=61.9±22.4 weeks), none of the individual SGAs outperformed FGAs (mainly haloperidol) regarding study-defined relapse, except for isolated, single trial-based superiority, and except for risperidone's superiority at 3 and 6 months when requiring ≥3 trials. Grouped together, however, SGAs prevented relapse more than FGAs (29.0 versus 37.5%, RR=0.80, CI: 0.70-0.91, P=0.0007, I(2)=37%; NNT=17, CI: 10-50, P=0.003). SGAs were also superior regarding relapse at 3, 6 and 12 months (P=0.04, P<0.0001, P=0.0001), treatment failure (P=0.003) and hospitalization (P=0.004). SGAs showed trend-level superiority for dropout owing to intolerability (P=0.05). Superiority of SGAs regarding relapse was modest (NNT=17), but confirmed in double-blind trials, first- and multi-episode patients, using preferentially or exclusively raw or estimated relapse rates, and for different haloperidol equivalent comparator doses. There was no significant heterogeneity or publication bias. The relevance of the somewhat greater efficacy of SGAs over FGAs on several key outcomes depends on whether SGAs form a meaningful group and whether mid- or low-potency FGAs differ from haloperidol. Regardless, treatment selection needs to be individualized considering patient- and medication-related factors.

Oral antipsychotic update: a brief review of new and investigational agents for the treatment of schizophrenia

Antipsychotics are the mainstay of treatment for patients with schizophrenia. However, these medications only work if they are taken and perhaps work best if they are taken for longer periods of time than seen in typical research trials. Here we explore the idea of "time as drug" by reviewing the data showing the potential benefits of long-term antipsychotic use. We also discuss the utility of depot antipsychotic formulations for improving the chances of attaining long-term therapeutic results.

Body weight and metabolic adverse effects of asenapine, iloperidone, lurasidone and paliperidone in the treatment of schizophrenia and bipolar disorder: a systematic review and exploratory meta-analysis

BACKGROUND

The introduction of second-generation antipsychotics (SGAs) over the past 2 decades generated considerable optimism that better antipsychotic treatments for schizophrenia and bipolar disorder were possible. SGAs offer several tolerability benefits over first-generation antipsychotics (FGAs), particularly with respect to extrapyramidal symptoms. However, SGAs can induce serious metabolic dysregulations, especially in drug-naive, first-episode, and child and adolescent populations, with olanzapine and clozapine having the highest propensity to cause these abnormalities. In this context, newer SGAs were developed to further improve the adverse effect burden of available agents. However, until now, the metabolic risk profile of the newly approved SGAs - asenapine, iloperidone, lurasidone and paliperidone (paliperidone extended release and paliperidone palmitate) - has not been compared.

OBJECTIVE

The objective of this systematic review and exploratory meta-analysis was to assess the effects of asenapine, iloperidone, lurasidone and paliperidone on body weight and other metabolic parameters (cholesterol, triglycerides and glucose), as this information is relevant to guide clinical decision making.

METHOD

A systematic literature search (1966-March 2012), using the Cochrane Central Register of Controlled Trials and MEDLINE, CINAHL and EMBASE databases, was conducted for randomized, placebo-controlled and head-to-head clinical trials of asenapine, iloperidone, lurasidone and paliperidone. Published and unpublished data on changes in body weight and glucose and lipid metabolism parameters were extracted. For placebo-controlled, short-term (≤12 weeks) and longer-term (>12 weeks) trials with available data on ≥7% weight increase compared with pre-treatment weight, or mean weight change with standard deviation, a formal meta-analysis was performed, estimating the pooled effect size (represented as relative risk [RR], numbers-needed-to-harm [NNH] and weighted mean difference [WMD]). An exploratory meta-analysis was also performed for the other metabolic variables (cholesterol, triglycerides and glucose). Data from active- and placebo-controlled studies were used for a pooled comparison of simple mean changes in weight, cholesterol, triglyceride and glucose levels.

RESULTS

Fifty-six trials (n = 21 691) in schizophrenia (N = 49, n = 19 299) or bipolar disorder (N = 7, n = 2392) were identified (asenapine: N = 9, iloperidone: N = 11, lurasidone: N = 8, paliperidone: N = 28). Most of the trials (64.3%) were of ≤12 weeks' duration. In the short-term trials, compared with placebo, a ≥7% weight increase was statistically significantly (p < 0.05) most prevalent for asenapine (5 trials, n = 1360, RR = 4.09, 95% confidence interval [CI] 2.25, 7.43, NNH = 17), followed by iloperidone (4 trials, n = 1931, RR = 3.13, 95% CI 2.08, 4.70, NNH = 11) and paliperidone (12 trials, n = 4087, RR = 2.17, 95% CI 1.64, 2.86, NNH = 20). The effect of lurasidone on body weight (6 trials, n = 1793, RR = 1.42, 95% CI 0.87, 2.29) was not statistically significant. Short-term weight gain was statistically significantly (p < 0.001) greater than placebo with iloperidone (1 trial, n = 300, +2.50 kg, 95% CI 1.92, 3.08), paliperidone (15 trials, n = 3552, +1.24 kg, 95% CI 0.91, 1.57), asenapine (3 trials, n = 751, +1.16 kg, 95% CI 0.83, 1.49), as well as with lurasidone (5 trials, n = 999, +0.49 kg, 95% CI 0.17, 0.81, p < 0.01). Sufficient meta-analysable, longer-term, weight change data were only available for asenapine and paliperidone, showing statistically significantly (p < 0.001) greater weight gain versus placebo for both drugs (asenapine, 3 trials, n = 311, +1.30 kg, 95% CI 0.62, 1.98; paliperidone, 6 trials, n = 1174, +0.50 kg, 95% CI 0.22, 0.78). Although statistically significant, in general, no clinically meaningful differences were observed between the four newly approved SGAs and placebo regarding the mean change from baseline to endpoint in cholesterol levels in short-term trials, with the exception of iloperidone for total cholesterol (1 trial, n = 300, +11.60 mg/dL, 95% CI 4.98, 18.22, p ≤ 0.001), high-density cholesterol (1 trial, n = 300, +3.6 mg/dL, 95% CI 1.58, 5.62, p < 0.001) and low-density cholesterol (1 trial, n = 300, +10.30 mg/dL, 95% CI 4.94, 15.66, p < 0.001) and with the exception of lurasidone for high-density cholesterol (5 trials, n = 1004, +1.50 mg/dL, 95% CI 0.56, 2.44, p < 0.01). Asenapine increased total cholesterol statistically significantly (p < 0.05) during longer-term treatment (1 trial, n = 194, +6.53 mg/dL, 95% CI 1.17, 11.89). Regarding triglycerides, only short-term (3 trials, n = 1152, +1.78 mg/dL, 95% CI 0.40, 3.17, p < 0.01) and longer-term treatment with paliperidone (4 trials, n = 791, -0.20 mg/dL, 95% CI -0.40, -0.01, p < 0.05) had a statistically, but not clinically, significant effect. Statistically significant changes in glucose levels were noticed during short-term treatment with asenapine (2 trials, n = 379, -3.95 mg/dL, 95% CI -7.37, -0.53, p < 0.05) and iloperidone (1 trial, n = 300, +6.90 mg/dL, 95% CI 2.48, 11.32, p < 0.01), and during long-term treatment with paliperidone (6 trials, n = 1022, +3.39 mg/dL, 95% CI 0.42, 6.36, p < 0.05).

CONCLUSION

While preliminary data suggest the lowest weight gain potential with lurasidone and potentially relevant short-term metabolic effects for asenapine and iloperidone, data are still too sparse to comprehensively evaluate the metabolic safety of the newly approved SGAs. Therefore, there is a clear need for further controlled studies to evaluate whether these agents are less problematic regarding treatment-emergent weight gain and metabolic disturbances than other currently available antipsychotics.

Comparative effectiveness of switching antipsychotic drug treatment to aripiprazole or ziprasidone for improving metabolic profile and atherogenic dyslipidemia: a 12-month, prospective, open-label study

We studied the effects of switching antipsychotic drug-treated patients with schizophrenia or bipolar disorder who evidenced adverse metabolic side effects as indicated by a triglyceride/high-density lipoprotein ratio (TG/HDL) ≥ 3.5 to aripiprazole (ARIP; 5-30 mg/day, n = 24) or ziprasidone (ZIP; 40-160 mg/day, n = 28). Anthropometric and metabolic measures, psychopathology, quality of life and motor adverse effects were assessed over a 52-week period with evaluations at baseline, 6, 12, 26 and 52 weeks. There were statistically significant improvements in body weight, body mass index (BMI), TG, HDL and TG/HDL which did not differ between treatments. However, numerous secondary measures including weight and BMI, and the proportion of patients who lost ≥ 7% or who no longer met criteria for obesity, favored ZIP over ARIP. Decreases in total cholesterol and increases in HDL-cholesterol also favored ZIP. On the other hand, decreases in TG/HDL ratio and reduction in HgbA1c favored ARIP. There were no significant time or group × time interaction effects for most psychopathology measures; however, Global Assessment of Functioning Scores favored ARIP at 6 and 12 months. We conclude that switching patients with evidence of metabolic side effects to either ARIP or ZIP may be beneficial for some, but not all metabolic measures, with minimal risk of worsening of psychopathology and possibly some benefit in that regard as well.

Iloperidone, asenapine and lurasidone: a primer on their current status

INTRODUCTION

Three newer atypical antipsychotic drugs were FDA-approved in 2009 and 2010 in the following order: iloperidone, asenapine and lurasidone. The three drugs are indicated for the treatment of acute schizophrenia. Asenapine is also approved for treatment of manic or mixed episodes associated with bipolar I disorder, for the maintenance treatment of schizophrenia and as an adjunctive therapy with lithium or valproate for the acute treatment of manic or mixed episodes associated with bipolar I disorder in adults.

AREAS COVERED

This review compares and contrasts the current preclinical, clinical, safety and tolerability profiles of the three newer drugs, as reported in published preclinical and clinical studies, product labels, poster presentations and press releases.

EXPERT OPINION

Preclinical studies have reported that the three drugs have variable affinities for a wide range of neurotransmitter receptors, and are active in animal models predictive of antipsychotic activity. Asenapine is the first antipsychotic to be administered sublingually, whereas iloperidone requires titration to minimize orthostatic hypotension. Asenapine and lurasidone are associated with dose-related akathisia, whereas iloperidone is not. The three drugs appear to have relatively benign metabolic profiles. The availability of the three novel antipsychotics should provide additional options for improved treatment of schizophrenia and other psychotic disorders.

World Federation of Societies of Biological Psychiatry (WFSBP) Guidelines for Biological Treatment of Schizophrenia, part 1: update 2012 on the acute treatment of schizophrenia and the management of treatment resistance

These updated guidelines are based on a first edition of the World Federation of Societies of Biological Psychiatry Guidelines for Biological Treatment of Schizophrenia published in 2005. For this 2012 revision, all available publications pertaining to the biological treatment of schizophrenia were reviewed systematically to allow for an evidence-based update. These guidelines provide evidence-based practice recommendations that are clinically and scientifically meaningful and these guidelines are intended to be used by all physicians diagnosing and treating people suffering from schizophrenia. Based on the first version of these guidelines, a systematic review of the MEDLINE/PUBMED database and the Cochrane Library, in addition to data extraction from national treatment guidelines, has been performed for this update. The identified literature was evaluated with respect to the strength of evidence for its efficacy and then categorised into six levels of evidence (A-F; Bandelow et al. 2008b, World J Biol Psychiatry 9:242). This first part of the updated guidelines covers the general descriptions of antipsychotics and their side effects, the biological treatment of acute schizophrenia and the management of treatment-resistant schizophrenia.

Iloperidone (Fanapt®), a novel atypical antipsychotic, is a potent HERG blocker and delays cardiac ventricular repolarization at clinically relevant concentration

QT interval prolongation on the electrocardiogram (ECG) has extensively been reported with iloperidone, a novel antipsychotic drug. The objective of the present study was to evaluate the effects of iloperidone on cardiac ventricular repolarization at three different levels; in vitro, ex vivo and in vivo. (1) In vitro level: whole-cell patch-clamp experiments were performed on HERG-transfected HEK293 cells exposed to iloperidone 0.01-1 μmol/L (n = 35 cells, total) to assess drug effect on HERG current. (2) Ex vivo level: Langendorff retroperfusion experiments were performed on isolated hearts from male Hartley guinea pigs (n = 7) exposed to iloperidone 100 nmol/L with/without chromanol 293B 10 μmol/L to assess drug-induced prolongation of monophasic action potential duration measured at 90% repolarization (MAPD(90)). (3) In vivo level: ECG recordings using wireless cardiac telemetry were performed in guinea pigs (n = 5) implanted with radio transmitters and treated with a single oral gavage dose of iloperidone 3 mg/kg. (1) Patch-clamp experiments revealed an estimated IC50 for iloperidone on HERG current of 161 ± 20 nmol/L. (2) While pacing the hearts at stimulation cycle lengths of 200 or 250 ms, or during natural sinus rhythm (no external pacing), iloperidone 100 nmol/L prolonged MAPD(90) by respectively 9.2 ± 0.9, 11.2 ± 1.6 and 21.4 ± 2.3 ms. After adding chromanol 293B, MAPD(90) was further prolonged by 7.3 ± 3.3, 11.5 ± 2.3 and 29.2 ± 6.7 ms, respectively. (3) Iloperidone 3mg/kg p.o. caused a maximal 42.7 ± 10.2 ms prolongation of corrected QT interval (QTc(F)), 40 min after administration. Iloperidone prolongs the QT interval, the cardiac action potentials and is a potent HERG blocker. Patients are at increased risk of cardiac proarrhythmia during iloperidone treatment, as this drug possesses significant cardiac repolarization-delaying properties at clinically relevant concentration.

Quantifying clinical relevance in the treatment of schizophrenia

BACKGROUND

To optimize the management of patients with schizophrenia, quantification of treatment effects is crucial. While in research studies, the use of quantitative assessments is ubiquitous, this is not the case in routine clinical practice, creating an important translational practice gap.

OBJECTIVE

The aim of this study was to examine the relevance, methodology, reporting, and application of measurement-based approaches in the management of schizophrenia.

METHODS

We summarized methodological aspects in the assessment of therapeutic and adverse antipsychotic effects in schizophrenia, including definitions and methods of measurement-based assessments and factors that can interfere with the valid quantification of treatment effects. Finally, we proposed pragmatic and clinically meaningful ways to measure and report treatment outcomes.

RESULTS

Although rating scales are ubiquitous in schizophrenia research and provide the evidence base for treatment guidelines, time constraints and lack of familiarity with and/or training in validated assessment tools limit their routine clinical use. Simple but valid assessment instruments need to be developed and implemented to bridge this research-practice gap. In addition, results from research trials need to be communicated in clinically meaningful ways, including the reporting of effect sizes, numbers-needed-to-treat and -harm, confidence intervals, and absolute risk differences. Some important outcomes, such as treatment response, should be reported in escalating intervals using incrementally more stringent psychopathology improvements. Even with quantification, it remains challenging to weigh individual efficacy and adverse effect outcomes against one another and decide on the targeted or desired improvement or outcomes while also incorporating these in patient-centered and shared decision methods.

CONCLUSIONS

Quantification of treatment effects in schizophrenia is relevant for patient management, research, and the evaluation of health care systems. Beyond consensus about meaningful outcomes definitions, reporting strategies, pragmatic tool development and implementation, the discovery of novel treatment mechanisms and related biomarkers is hoped to advance measurement-based approaches in schizophrenia and thereby improve patient outcomes.

Iloperidone for the management of adults with schizophrenia

BACKGROUND

Iloperidone is a second-generation antipsychotic drug approved in May 2009 by the US Food and Drug Administration (FDA) for the acute treatment of schizophrenia in adults. It is a piperidinyl-benzisoxazole derivative with mixed serotonin (5HT2A) and D2 dopamine antagonist properties.

OBJECTIVE

The purpose of this article was to review the pharmacology, pharmacokinetics, efficacy, safety, and role in treatment for iloperidone in schizophrenia.

METHODS

Scientific and clinical data were collected through searches of PubMed, ClinicalTrials.gov, International Pharmaceutical Abstracts, and the FDA, using the search term iloperidone, and limited to English-language articles. Reference lists were reviewed for additional publications. Dates included the beginning of the database through 2010. No limits were placed on study design.

RESULTS

In a 4-week Phase III trial, iloperidone 12 mg twice daily lowered the Positive and Negative Syndrome Scale (PANSS) total scores to a significantly greater extent than did placebo (-12 vs -7.1; P < 0.01). The ziprasidone active control also separated from placebo (-12.3 vs -7.1; P < 0.05). A pooled analysis of 3 Phase III trials compared iloperidone in divided doses to placebo. The primary outcome was reduction in PANSS scores. Study 1 included iloperidone 4, 8, or 12 mg/d, haloperidol as an active control, and placebo. The PANSS reduction in the 12 mg/d group was significantly greater at end point versus baseline when compared with placebo (-9.9 vs -4.6; P = 0.047). Study 2 included iloperidone 4 to 8 mg/d or 10 to 16 mg/d, risperidone 4 to 8 mg/d, or placebo. The primary efficacy measure was change from baseline to end point in the Brief Psychiatric Rating Scale (BPRS). Improvement from baseline on all iloperidone doses was significantly greater than with placebo (4-8 mg/d group: -6.2, P = 0.012; 10-16 mg/d group: -7.2, P = 0.001; placebo, -2.5). Study 3 included iloperidone 12 to 16 mg/d, risperidone 6 to 8 mg/d, and placebo. The results on the primary efficacy variable, reduction in the BPRS score, was not significant for the 12 to 16 mg/d group versus placebo (-7.1 vs -5.0; P = 0.09), but was significant for the 20 to 24 mg/d iloperidone group (-8.6 vs -5.0; P = 0.01) and for the risperidone group (-11.5 vs 5.0; P < 0.001). A 52-week maintenance trial included iloperidone versus haloperidol as an active control. The primary efficacy variable was time to relapse. Comparison of mean time to relapse of the 2 arms showed no significant difference. The most common adverse events (AEs) associated with iloperidone were dizziness (5.1%-23.2%), dry mouth (5.2%-10.4%), somnolence (4%-13%), and dyspepsia (4.8%-7.8%). AEs appeared dose related. Prescribing information recommends a starting dosage of 1 mg twice daily and then titrated over 7 days to reach a target dosage of 12 to 24 mg/d. The titration is necessary to reduce the risk of orthostatic hypotension-related dizziness.

CONCLUSIONS

Data support that when titrated slowly to a therapeutic dosage, iloperidone is generally well tolerated, has a favorable safety profile, and is an effective treatment option in patients with schizophrenia. Its place in therapy and performance in a typical patient population remain to be established. Slow initial titration and twice-daily dosing are potential disadvantages.

Efficacy of iloperidone in schizophrenia: a PANSS five-factor analysis

BACKGROUND

The Positive and Negative Syndrome Scale (PANSS) total score is widely used to assess antipsychotic efficacy, however schizophrenia is a multi-dimensional disorder. We conducted a 5-factor analysis for evaluating the efficacy of iloperidone vs. placebo across these different domains in the treatment of schizophrenia.

METHOD

The 5-factor model was determined from pooled data from 7 clinical trials (4 placebo- and active-controlled and 3 non-inferiority active-comparator trials of iloperidone) in schizophrenia (N=3580).Five factors were derived (excitement/hostility [P4,P7,G8,G14], depression/anxiety [G1,G2,G3,G4,G6], cognition [P2,N5,N7,G5,G10,G11,G12,G13,G15], positive [P1,P3,P5,P6,G9], and negative [N1,N2,N3,N4,N6,G7,G16]) from a factor analysis on the covariance matrix of 30 baseline PANSS items using a varimax rotation; factors retained had eigenvalues of ≥ 0.5. These newly derived 5 factors differ only slightly from other 5-factor analyses published by others using different datasets. The analysis of covariance model was then applied to assess these efficacy outcomes from the 4-6 week double-blind placebo and active controlled clinical trials of iloperidone.

RESULTS

Based on the placebo-controlled trials, iloperidone improvements from baseline (least squared mean change ± standard error) were as follows: excitement/hostility, 0.4 ± 0.21 for 10-16 mg, 0.6 ± 0.43 for 20-24 mg vs. -1.0 ± 0.23 for placebo; P<0.001 for both iloperidone doses vs. placebo; depression/anxiety, 1.9 ± 0.21 for 10-16 mg, 1.9 ± 0.41 for 20-24 mg vs. 1.1 ± 0.22 for placebo; P<0.05 for 10-16 mg dose vs. placebo; cognition, 2.8 ± 0.35 for 10-16 mg, 3.9 ± 0.69 for 20-24 mg vs. 1.6 ± 0.38 for placebo; P<0.05 for both iloperidone doses vs. placebo; positive, 3.7 ± 0.26 for 10-16 mg, 4.1 ± 0.53 for 20-24 mg vs. 2.7 ± 0.29 for placebo; P<0.05 for both iloperidone doses vs. placebo; and negative, 2.2 ± 0.29 for 10-16 mg, 2.5 ± 0.58 for 20-24 mg vs. 1.3 ± 0.32 for placebo; P<0.05 for 10-16 mg vs. placebo. Active controls validated iloperidone efficacy.

CONCLUSIONS

Iloperidone demonstrated positive treatment effects on these newly derived PANSS factors. The 10-16 mg and 20-24 mg dose groups had similar efficacy on the PANSS factors, with the exception of the depression/anxiety and negative factors, on which the 10-16 mg dose group showed statistical separation from placebo and the 20-24 mg dose group did not. At 6 weeks, the lack of separation from placebo for the higher dose group may have been due to the much smaller sample size in that group.

Iloperidone: A new drug for the treatment of schizophrenia

PURPOSE

The pharmacology, pharmacokinetics, pharmacogenomics, clinical efficacy, and safety and tolerability profile of iloperidone for the treatment of schizophrenia are reviewed.

SUMMARY

Iloperidone is an atypical antipsychotic that recently received marketing approval from the Food and Drug Administration for the acute treatment of schizophrenia. Iloperidone is a pure antagonist and the first antipsychotic to have pharmacogenomic studies indicate predictive response based on six identified polymorphisms. Pharmacokinetic studies have determined that iloperidone is well absorbed orally, with a bioavailability of 96%. Phase II and III clinical trials have shown iloperidone to improve symptoms of schizophrenia, based on the Positive and Negative Symptom Scale, Brief Psychiatric Rating Scale, and Clinical Global Impressions-Severity scores (p < 0.05). Iloperidone has established tolerability at recommended dosages of up to 24 mg daily; however, the dosage must be slowly increased over seven days, and twice-daily administration is required to avoid orthostatic hypotension. The most common adverse effects associated with iloperidone were dizziness, dry mouth, fatigue, nasal congestion, orthostatic hypotension, somnolence, tachycardia, and weight gain. Safety studies have also found that iloperidone increases the risk of Q-Tc interval prolongation, similar to that seen with ziprasidone. Minimal changes in glucose and lipid abnormalities were seen in short-term (4- and 6-week) and long-term (52-week) studies, indicating a low chance of metabolic disturbance with iloperidone.

CONCLUSION

Iloperidone may be a viable and safe option for the treatment of schizophrenia in adult patients, especially for patients who cannot tolerate other antipsychotic agents. However, iloperidone lacks a clear benefit over other antipsychotic agents.

Emerging drugs for schizophrenia

INTRODUCTION

Since the development of clozapine, scores of antipsychotics have been introduced. These are, with one exception (aripiprazole), based on the pharmacological principle of 5-HT(2)/dopamine antagonism. Research on other treatment targets, which, in part, influence dopaminergic pathways directly or indirectly, is mounting. Managing psychotic symptoms is only one facet of successful treatment of schizophrenia. Effective remedies against negative symptoms and cognitive deficits are still an unmet clinical need.

AREAS COVERED

With the focus on the topics mentioned above, the authors briefly review the latest clinical research organized on the basis of receptor systems and other drug targets, which are discussed to be involved in the pathophysiology of schizophrenia.

EXPERT OPINION

In conclusion, although clinicians will have to have considerable patience before truly novel anti-schizophrenia treatments become obtainable, a number of interesting leads with considerable theoretical potential are being explored. As yet, it is difficult to predict which of these mechanisms will effectively augment the currently available treatments.

Iloperidone: chemistry, pharmacodynamics, pharmacokinetics and metabolism, clinical efficacy, safety and tolerability, regulatory affairs, and an opinion

IMPORTANCE OF THE FIELD

Iloperidone is a newly commercialized second-generation (atypical) antipsychotic approved for the acute treatment of schizophrenia in adults.

AREAS COVERED IN THIS REVIEW

the purpose of this review is to describe the pharmacokinetic profile of iloperidone and its clinical implications in the treatment of schizophrenia. Background information is also provided regarding chemistry, pharmacodynamics, clinical efficacy and safety data, and regulatory affairs.

WHAT THE READER WILL GAIN

the reader will have an understanding of the pharmacokinetics and overall metabolism of iloperidone within the context of efficacy and safety.

TAKE HOME MESSAGE

time to peak plasma concentration occurs in 2 - 4 h but elimination half-life is 18 h for extensive CYP2D6 metabolizers and 33 h for poor CYP2D6 metabolizers, suggesting that once or twice daily dosing would be feasible. Dizziness and/or postural hypotension are the limiting factors for how fast iloperidone can be titrated, and is explained by iloperidone and its metabolites' norepinephrine alpha 1 antagonism. Efficacy of iloperidone appears similar to that for ziprasidone and haloperidol, but iloperidone may be inferior in efficacy to risperidone. Iloperidone can prolong the ECG QT interval. The tolerability profile of iloperidone is noteworthy in terms of modest weight gain, no medically important changes in lipid and glucose, little in the way of prolactin elevation, and an absence of extrapyramidal adverse effects, including akathisia.

One-year open-label safety and efficacy study of paliperidone extended-release tablets in patients with schizophrenia

INTRODUCTION

This 52-week open-label extension (OLE) to a double-blind placebo-controlled recurrence prevention study examined the long-term safety and efficacy of flexibly-dosed paliperidone extended-release (ER) tablets in patients with schizophrenia.

METHODS

Patients entering the OLE either entered from the double-blind phase (placebo or paliperidone ER treatment) or entered directly from the run-in or stabilization phase (paliperidone ER) of the earlier study. During the OLE, patients were treated with flexibly-dosed paliperidone ER (3-15 mg/day; 9 mg starting dose). Safety and tolerability assessments included incidence of adverse events and extrapyramidal symptoms. Efficacy was also assessed.

RESULTS

The study population (n=235) was predominantly men (66%), 18-58 years of age. Twelve patients (5%) experienced an adverse event requiring treatment discontinuation. One or more serious treatment-emergent adverse events were reported in 13 patients (6%). There was one death. The mean Positive and Negative Syndrome Scale total score decreased from open-label baseline to endpoint for all groups, regardless of previous double-blind treatment (placebo or paliperidone ER).

CONCLUSION

This year-long OLE provides information on the long-term safety and tolerability of paliperidone ER in patients with schizophrenia. The resulting safety and tolerability profile was similar to that seen in earlier short-term studies.

Iloperidone—A Second-Generation Antipsychotic for the Treatment of Acute Schizophrenia

Objective:

To review the pharmacology, efficacy, and tolerability of iloperidone, a second-generation antipsychotic, in the treatment of acute schizophrenia in adults.

Data Sources:

English-language articles were obtained via MEDLINE (1966-March 2010) and International Pharmaceutical Abstracts (1970-March 2010) searches using the key words iloperidone, acute schizophrenia, atypical antipsychotics, second-generation antipsychotics, HP 873, P88–8991, P95–12113, and Fanapt. Bibliographies of selected articles were used to identify additional sources.

Study Selection and Data Extraction:

Available published articles reporting the results of human studies of iloperidone were reviewed for inclusion in this article. Additional information regarding pharmacology, adverse events, contraindications, and precautions was obtained from the manufacturer's prescribing information.

Data Synthesis:

Iloperidone is a second-generation antipsychotic approved for the treatment of acute schizophrenia in adults. Iloperidone is well absorbed upon oral administration, highly protein bound, and metabolized primarily by CYP3A4 and 2D6. Phase 3 clinical trials evaluating the efficacy of iloperidone demonstrated significantly higher response rates with iloperidone compared with placebo in the treatment of positive, negative, and cognitive symptoms associated with acute schizophrenia when the drug was given in doses up to 24 mg daily. Dizziness, dry mouth, and nausea were the most commonly reported adverse events and appear to be dose related. Additional adverse events occurring in 5% or more of patients include orthostatic hypotension, somnolence, tachycardia, fatigue, nasal congestion, and weight increase. Iloperidone should be titrated slowly over a 7-day interval to avoid the potential for orthostatic hypotension. Product labeling includes a black box warning against the use of iloperidone in dementia-related psychosis and precautions regarding QT interval prolongation.

Conclusions:

Iloperidone is an effective treatment for the symptoms of acute schizophrenia in adults. Additional studies are needed to assess comparative effectiveness with other pharmacologic treatments of schizophrenia, long-term efficacy, and long-term safety.

Iloperidone for the treatment of schizophrenia

OBJECTIVE

To review the pharmacology, pharmacokinetics, efficacy, and safety data of iloperidone for the treatment of schizophrenia.

DATA SOURCES

Data were selected by searching Pre-MEDLINE, MEDLINE, and International Pharmaceutical Abstracts (1966-January 2010). Abstracts, scientific posters, and unpublished data provided by the manufacturer in the English language were also assessed.

STUDY SELECTION AND DATA EXTRACTION

All published data including pharmacologic, pharmacokinetic, pharmacodynamic, and clinical studies related to iloperidone were considered for inclusion. Selected studies included randomized controlled trials, abstracts, and posters presented at national scientific meetings providing pertinent data.

DATA SYNTHESIS

Iloperidone is a benzisoxazole phenylethanone with a higher affinity for serotonin-2a than dopamine-2 receptors. The recommended therapeutic total daily dose is 12-24 mg divided in 2 doses titrated over 1 week to avoid orthostasis. Acute, 6-week, randomized, placebo-controlled, and active-controlled studies demonstrated iloperidone's efficacy in reducing psychotic symptoms according to changes in the total positive and negative symptom scale (PANSS-T) score from baseline. A long-term maintenance trial demonstrated similar efficacy with haloperidol in preventing time to relapse. Pharmacogenomic studies reported possible single nucleotide polymorphisms related to QT interval prolongation and efficacy with iloperidone. Common adverse effects included dizziness, dry mouth, and sustained orthostasis occurring more frequently with higher doses. Weight gain is possible at any dose. Additionally, studies showed that QTc interval prolongation may be dose related. The incidence of extrapyramidal symptoms appears to be low across all dosage ranges; however, akathisia may be more frequent with higher doses.

CONCLUSIONS

Iloperidone demonstrated efficacy in acute exacerbations and long-term maintenance in adults with schizophrenia. Caution may be warranted in elderly patients and patients with cardiac disease, due to orthostasis. Further studies regarding pharmacogenomic testing related to the drug's efficacy and tolerability are needed to justify its routine use in practice.

New atypical antipsychotics for schizophrenia: iloperidone

The optimal treatment of schizophrenia poses a challenge to develop more effective treatments and safer drugs, to overcome poor compliance, discontinuation and frequent switching with available antipsychotics. Iloperidone is a new dopamine type 2/serotonin type 2A (D(2)/5-HT(2A)) antagonist structurally related to risperidone, expected to give better efficacy with less extrapyramidal symptoms than D(2) receptor antagonist antipsychotics. In double-blind phase III trials iloperidone reduced the symptoms of schizophrenia at oral doses from 12 to 24 mg. It was more effective than placebo in reducing positive and negative syndrome total score and Brief Psychiatric Rating scale scores; it was as effective as haloperidol and risperidone in post-hoc analysis. Its long-term efficacy was equivalent to that of haloperidol. The most common adverse events were dizziness, dry mouth, dyspepsia and somnolence, with few extrapyramidal symptoms and metabolic changes in short- and long-term studies in adults. Akathisia was rare, but prolongation of the corrected QT (QTc) interval was comparable to haloperidol and ziprasidone, which is of particular concern. Further comparative studies are needed to clarify the benefit/risk profile of iloperidone and its role in the treatment of schizophrenia.